1. Field of the Invention
The present invention relates to a sample analyzer in which a gas from an extraction furnace is introduced into a detector to be analyzed.
2. Description of Related Art
One of the conventional uses for sample analyzers is for analyzing oxygen and nitrogen contained in a sample such as metal. A sample analyzer may be used to analyze a sample such as oxide ceramics and nitride ceramics containing a relatively large amount of oxygen and nitrogen therein, the so-called high-concentration samples. A buffer vessel, for suppressing a momentary concentration of gases (Co, N.sub.2) generated in an extraction furnace, must be used between the extraction furnace and the detector. In cases where a low-concentration sample, such as iron or steel, containing a relatively small amount of oxygen and nitrogen, or ceramics containing a small amount of oxygen and nitrogen as impurities is analyzed, the buffer vessel must be removed.
It is labor intensive to install and remove the buffer vessel each time the analytical sample is switched from a high-concentration sample to a low-concentration sample. Moreover, time is required for the detector to stabilize each time the buffer vessel is installed or removed. The result is that the analysis takes a long time. In cases where a high-concentration and a low-concentration come at random, the inconvenience is compounded and use of the analyzer becomes particularly difficult.